REPAIR-AMI: Intracoronary Progenitor Cells in Acute Myocardial Infarction (AMI)

Inclusion Criteria: * Patients with acute myocardial infarction (ST elevation in at least 2 leads \>= 0.2 mV in V1,V2 or V3 or \>= 0.1 mV in other leads), treated by one of the following procedures * Either acute PCI with stent implantation within 24 hours after symptom onset or * treatment with thrombolysis within 12 hours of symptom onset followed by PCI with stent implantation within 24 hours after thrombolysis. * Acute PCI / stent implantation has been successful (residual stenosis visually \< 30% and TIMI flow \>= 2). * At the time of inclusion patient does no longer require i.v. catecholamines or mechanical hemodynamic support (aortic balloon pump) * Significant regional wall motion abnormality in LV angiogram at the time of acute PCI (ejection fraction \<= 45% on visual estimation). * Maximal CK elevation \>= 400 U/l (measured at 37° C) with significant MB fraction \> 6% * Age 18 - 80 Years * Written informed consent Exclusion Criteria: * Regional wall motion abnormality outside the area involved in the index acute myocardial infarction. * Need to revascularize additional vessels, outside the infarct artery. * Arteriovenous malformations or aneurysms * Active infection (CRP \> 10 mg/dl) now, or fever or diarrhea within last 4 weeks. * Chronic inflammatory disease * HIV infection or active hepatitis * Neoplastic disease without documented remission within the past 5 years. * Cerebrovascular insult within 3 months * Impaired renal function (creatinine \> 2 mg/dl) at the time of cell therapy * Significant liver disease (GOT \> 2x upper limit) or spontaneous INR \> 1,5) * Anemia (hemoglobin \< 8.5 mg/dl) * Platelet count \< 100.000/µl * Hypersplenism * Known allergy or intolerance to clopidogrel, heparin or abciximab. * History of bleeding disorder * Gastrointestinal bleeding within 3 months * Major surgical procedure or traumata within 2 months * Uncontrolled hypertension * Pregnancy * Mental retardation * Previously performed stem / progenitor cell therapy * Participation in another clinical trial within the last 30 days.